From the Associated Press:
U.S. and Canadian children will be exempt from new rules that will require travelers to show passports when entering the U.S. at land or sea borders, a move the Bush administration said is aimed at helping families and school groups.

The new passport requirements will take effect as soon as January 2008. In a change from earlier plans, U.S. and Canadian citizens ages 15 or younger with parental consent will be allowed to cross the borders at land and sea entry points with certified copies of their birth certificates rather than passports.

U.S. and Canadian citizens ages 16 through 18 traveling with school, religious, cultural or athletic groups and under adult supervision will also be allowed to travel with only their birth certificates.

Sen. Charles Schumer, D-N.Y., said he would introduce legislation that would delay implementation of the passport requirement until at least June 2009. The bill also would require studies on the economic impact of the initiative on each border state, and to test an enhanced driver's license program as an alternative to passports in at least one location.

Any alternative to passports would have to cost adults no more than $20 and be free for children, under the bill.

Beginning last Jan. 23, nearly all air travelers entering the U.S. who are citizens of Canada, Mexico, Bermuda or the Caribbean -- as well as returning American citizens -- have been required to display passports. Children entering the United States by air will still be required to show passports.